Multiple accounts

We have three separate accounts (me, hubby, son) This morning I did a ride, logged in correctly, all details on screen were me etc. Ride saved to Zwift and Strava. A few hours later, hubby did the same ride. He logged in correctly and his name and avatar were correct on the screen. He finished the ride and saved it BUT it saved to my Zwift account and wiped out my own morning ride. However, I can see both in my Strava account and both are under my name. Why would this happen?